KC 868-A16 RS485

[daudrimu]

Hello,
I am trying to connect a pressure sensor to my KC868-A16 board using RS485 communication. The sensor works via Modbus RTU, and I want the KC868-A16 to act as the master.
Here are the issues I am facing:

1. On the web configuration page of KC868, I can see General Protocol and Custom Protocol, but I am not sure which one I should use for the pressure sensor, since it is not listed in the default devices.
   
2. I have tested the RS485 line with a USB-RS485 adapter and Modbus Poll, and I can see the sensor replying with values (e.g. 500, 0, 500, …). So the sensor is working correctly.
   
3. When I try to scan for slave IDs from Python via the KC RS485, I only get timeout errors. TX is active, but RX never receives data.
   
4. I have already checked the wiring (A↔A, B↔B, and GND connected), baudrate, parity, stopbits, and slave ID, but still no communication between KC and the pressure sensor.
   

So my questions are:

• How should I configure KC868 in the web interface to read registers from the pressure sensor?
  
• Do I need to use General Protocol or Custom Protocol?
  
• Is there any example of how to set the registers mapping for an external Modbus RTU sensor?
  

Thanks in advance for your help!

[admin]

KCS firmware not use for customize RS485 sensor.
if you want use for home assistant, i suggest you config by ESPHome via modbus controller. You can also write your own Arduino code for your project.